SOLUTION: 6 persons worked 8 days to finish 3/5 of a building,. If 2 more persons join them , how may more days to complete the building?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: 6 persons worked 8 days to finish 3/5 of a building,. If 2 more persons join them , how may more days to complete the building?      Log On


   

Question 857592: 6 persons worked 8 days to finish 3/5 of a building,. If 2 more persons join them , how may more days to complete the building?
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
6 persons______________8 days______(3/5)job
1 person______________6*8 days_____(3/5)job

One person works at a rate of %28%283%2F5%29%2F%286%2A8%29%29%28jobs%2Fday%29.
Simplifying the one-person rate,
3%2F%285%2A6%2A8%29
highlight_green%283%2F%285%2A2%2A8%29%29----Not changing this form yet, since maybe not need to.

How many more days, if TWO more people join to help?
The remaining building job to do is %282%2F5%29, and now the number of people to do this work is 6%2B2=8, eight people to do this work.

The work rate for these eight people together is now 8%283%2F%282%2A5%2A8%29%29=3%2F%282%2A5%29=highlight_green%283%2F10%29 jobs per day.

Uniform rates equation for task completion or work rates goes as R*T=J for Rate, Time(in days here), Job(whatever is to be done to the building). Putting the numbers in place,
highlight%28%283%2F10%29%2At=2%2F5%29 where t is the number of days for this amount of job at that work rate.
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t=%282%2F5%29%2810%2F3%29=4%2F3=highlight%281%261%2F3%29 days more.